The invention relates to a device for determining at least one physical, chemical and/or biological characteristic of a liquid medium that has been introduced into a sealable container. The invention also relates to a method of determining at least one physical, chemical and/or biological characteristic of a liquid medium introduced into a sealable container.
Methods, particularly for examining the use-by date of for example foods in packaging, such as plastic packaging, are fundamentally known. Accordingly, such methods mainly relate to drinks or dairy products in the form of cheese or yoghurt, as well as meat, sweet products, spices and suchlike. By indicating a use-by date for the food, which is shown on its packaging for example, a statement can be made concerning the date by which the foodstuff in question should be consumed when properly stored with no loss or taste of quality and also without risk to health. However, a use-by date is not only shown on the packaging of relevant foods, but also the packaging of cosmetic products, which, as a rule, cannot be stored for more than approximately 2.5 years. As determining the use-by date is left to the discretion of the product manufacturer, from the relevant production series or batches individual samples are kept by means of which the quality of the entire batch or series of produced products can be proven. Such random sampling of the series or batch of products by means of individual product samples allows product manufacturers to carry out simple quality control of the manufactured product. If during product quality control a product of inadequate quality is identified, the manufacturer is able to block the entire production batch and prevent supply to the consumer.
Particularly in the drinks industry, the pressure present in the bottle as well as the material of the bottle itself, which can be made of glass, porcelain or plastic for example, are decisive for the quality and taste of the drinks themselves. For instance, particularly the carbon dioxide content (CO2 content) in the drinks is an important influencing factor with regard to the taste and use-by date of the drink or food. In order to be able to determine a physical characteristic, such as the colour, the density or the viscosity, in particular of a liquid or flowable medium such as a drink, or its chemical characteristics such as the carbon dioxide content and/or its biological characteristics such as the presence of bacteria, in addition to optimum sample preparation—for which a sufficiently large amount of time is required—an appropriate measuring method is also necessary which delivers reproducible measuring results. Additionally, all packaging influences on the quality of the liquid products must also be taken into consideration. Especially in view of the continuing trend to ever newer and more cost-effective types of packaging and packaging materials for packaging the liquid media, the determination and/or measurement of the physical, chemical and/or biological characteristics of the liquid medium is incomplete without taking into account the relevant packaging influences.